The ability to place a cleansing phase in physical contact with a structured aqueous phase and maintain stability for any period of time has proven to be a problem. The physical contact of a structured aqueous phase and a cleansing phase creates a situation where they are thermodynamically unstable.
One attempt at providing a stable, structured aqueous phase and cleansing phase within a personal cleansing product would be the use of dual-chamber packaging. These packages comprise separate cleansing compositions and structured aqueous compositions, and allow for the co-dispensing of the two in a single or dual stream. The separate structured aqueous composition and cleansing compositions thus remain physically separate and stable during prolonged storage and just prior to application, but then mix during or after dispensing to provide conditioning and cleansing benefits from a physically stable system. Although such dual-chamber delivery systems provide improved cleansing benefits versus conventional systems, it is often difficult to achieve consistent and uniform performance because of the uneven dispensing ratio between the cleansing phase and the structured aqueous phase. Additionally, these packaging systems add considerable cost to the finished product.
Another attempt at providing a cleansing and moisturizing benefit composition has been to formulate and package such compositions as disclosed in U.S. Pat. No. 6,534,456 issued to Hayward et al., on Mar. 18, 2003 describing extrudable multi-phase compositions comprising a lamellar phase and an isotropic phase. These exemplified compositions, however, contain water soluble colorants which tend to migrate from one phase to the other. The colorant can be a meaningful aspect of the product to the consumer, connoting both benefit and performance. For a multi-phase system, the colorant can serve to distinguish the two phases from each other. Traditionally, water soluble colorants, i.e. dyes, have been used to color cleansing systems. It has, however, been found that when the compositions of the two phases are chemically distinct, as described herein, color migration of certain commonly used colorants will serve to render multi-phase compositions less visibly distinct which, may decrease their appeal. Stability is integral in such application and thus, there still remains a need for a stable personal cleansing composition that provides cleansing and skin benefits patterned in physical contact within the same package.